Blowers for railway switches



May 12, 1959 M. w. KlsTLER 2,886,266

' BLowERs FOR' RAILWAY SWITCHES Filed Feb.-16. 1954 4 sheets-sheet 1 s .S um G RR Y ww O W L; e LLPI LF L M m v T llillln'ulnlldkm." IIIIIIIIILUUUHIIIIIIII .II|||||I|||II|||||HI|II| o -kwa vm T L F L N. M X A e M Y B m [FF 1 5 lf/ LF. .N .LF/ El 1 J1 j. V |ludzdw:l|dvdP||H|||h||hF||lhhunHnnhnlhhlrbvllahhunlHndlllhhi S I Q Q t @/Mh lm Q IL NM m m @E s k Q www Q w R J|h|. nl| Mw QM. Rv# dll d Sv Nw t. N Q n AL /l W\\ IR Sv 3v www M. w. KlsTLER BLOWERS FOR RAILWAY SWITCHES f May 12,1959

, 4 Sheets-Sheet 2 Filed Feb. 16. 1954 May l2, 1959 M. w. KlsTLER BLowERs FOR RAILWAY SWITCHES 4 sheets-sheet s Filed Feb. 16. 1954 iNvENToR. MAX w. msrLER BY M ATTORNEYS May 12,'1959 M w. KISTLERA 2,886,266

BLowERs FOR RAILWAY SWITCHES y l 'Filed Feb. 1e, 1954 4 sheets-sheet 4 United States Patent `2,886,266 Patented May 12, 1959 `ice BLOWERS FOR RAILWAY S/WITCHES Max W. Kistler, Rochester, N.Y., assignor to American Brake Shoe Company, New York, N.Y., a corporation of Delaware Application February 16, 1954, Serial No. 410,557

2 Claims. (Cl. 246-428) This invention relates to blowers for maintaining railway switches free of snow, debris and the like.

The successful operation of a railway switch is often impeded by accumulations of snow, debris and the like which packs between the stock rail and the switch point, such that the latter cannot engage during operation of the switch. Therefore, if a proper functioning of the vswitch is to be attained during inclement weather or other natural conditions giving rise to accumulations of debris between the switch point and the stock rail, it is necessary to provide the switch with a means for maintaining the same free of such obstructions. In the past, such means .have either been in the form of electrical resistance elements mounted on one of the rails for melting snow and ice, or a set of open gas flames arranged at the switch for the same purpose. However, operation of these prior devices is inherently accompanied by the melted snow or ice flowing in a stream to another point where freezing again occurs. This, it will be seen, is but a partial solution to the problem. Moreover, where electrical resistance elements are used, the system is somewhat delicate and subject to reoccu-rring malfunctions, and where gas llames have been resorted to, these are many times accidentally extinguished. ln addition, open gas flames in any event represent a fire hazard and are likely to cause overheating of adjacent switch parts.

Other arrangements have also been suggested but such have not been utilized commercially because they do not embody any practical means of control.

y The primary object of the present invention is to permit railway switch installations to be maintained free of snow, debris and the like by means of a pneumatic blower which possesses none of the objectionable features of the prior art devices mentioned above. A further object of this invention is to permit railway switch installations to be maintained free of snow, debris and the like by means of a pneumatic blower which can be operated by remote control and in which intermittent pulses of air under pressure are directed to the switch in an accurately timed relation that may be preselected in accordance with the weather conditions to be reckoned with.

, Other objects of the present invention are to permit railway switches to be maintained clean by means of a relatively inexpensive pneumatic blower apparatus; to reduce mechanical hazards at railway switch installations that have heretofore been inherent in switch cleaners of the prior art; and to eliminate the need for manual labor for policing railway switch installations during inclement weather.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments of the present invention and the principles thereof and what I now consider to be the best mode in which I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings: Fig. l is a plan view of a railway switch with which the novel blowing apparatus for the present invention is associated, wherein certain of the control and kindred apparatus for the blower associated therewith are partially diagrammatically illustrated without regard to scale;

Fig. 1A is an elevation of the air switch shown in Fig. 1 with the cover removed;

Fig. 2 is a transverse sectional view taken substantially on the line 2 2 on Fig. l;

Figs. 3 and 4 are views showing modified forms of control apparatus that may be employed;

Fig. 5 is a longitudinal sectional view taken substantially on the line 5 5 on Fig. l

Fig. 6 is a transverse sectional view taken substantially on the line 6 6 on Fig. 1, but showing the switch point engaged with the stock rail rather than spaced therefrom, as shown in Fig. 1;

Fig. 7 is a view drawn to an enlarged scale showing one of the nozzles and the mounting therefor on the blowing apparatus;

Fig. 8 is a vertical sectional view of the nozzle arrangement shown in Fig. 7;

Fig. 9 is a vertical sectional view drawn to an enlarged scale showing the discharge end of a nozzle;

Fig. 10 is a perspective view of a tool that may be advantageously employed in arranging a nozzle for the desired operation;

Fig. 11 is a partially diagrammatic plan view showing an arrangement to which resort may be advantageously had in an instance Where the novel blowing apparatus of the present invention is employed in association with a plurality of switches;

Fig. l2 is a partial view of a timer taken on the line 12-12 of Fig. 13; and I Fig. 13 is a view looking at the end of the timer shown in Fig. 12.

In the accompanying drawings, a track arrangement is shown including the usual stock rails 15 and 16 that have switch points as 17 and 18 associated therewith adapted to be actuated by conventional means for purposes well understood in the art. In the present instance, the novel blowing apparatus of the present invention for maintaining the space between the rails free of snow, debris and the like includes a pair of elongated manifolds 19 and 20, Fig. 1, for compressed air that are respectively mounted on the stock rails 15 and 16 on the inside faces thereof that are respectively disposed toward the switch points 17 and 18.

The present apparatus accomplishes cleaning of the railroad switch installation by means of pulses of compressed air of a certain duration with a certain lapse of time between pulses. Thus, dry snow may require one kind of pulse duration and rate, and wet snow may require pulses of different duration or rate or both. Likewise, accumulations of sand, leaves or like debris may require pulse durations and/ or rates of altogether different order. Another object of the present invention is to incorporate in railroad switch blower apparatus, timing means for independently regulating the duration of compressed air pulses and time lapses between pulses.

Each manifold comprises an elongated conduit that is adapted to be mounted on the web W, Fig. 6, of a rail as 15 beneath the head 21 thereof. These conduits as 19C, Figs. 5-7, are preferably elliptical so that atleast those portions of each conduit opposite the switch point 17 are desirably formed to be of reduced size in a horizontal plane. In any event, however, the size of each manifold conduit as 19C is so constructed as to insure that the vsame will be confined completely beneath the portion of the head 21 of the rail that extends inwardly of the web W, for so to do insures that the manifolds will not project beyond the head of the rails and interfere with the engagement of the switch point and stock rail as shown, for example, in Fig. 6. At suitable intervals along the extent of each manifold, openings are extended through the web of the rail whereby a bolt as 22 may be passed therethrough, such a bolt passing through an opening formed in a retaining clip as 23 that is adapted to engage a manifold as 19, a lock washer as 24 and a nut as 25 being provided to firmly clamp the clip 23 in position to retain the manifold in engagement with the web W ofthe rail as 15.

Air under pressure in the manifold conduits is to be directed into and along the space between theV switch point and stock rail in a substantially continuous stream to sweep out snow, debris and the like from between these rails, and for this purpose nozzles N are provided at spaced intervals along each conduit as 19C, these nozzles being arranged within the plane of such conduit and directed such as shown in Fig. 5. It has been found to be advantageous to locate the nozzles in related positions along the manifold so that the nozzles are spaced apart about fifteen inches, although it will be understood that resort could be had to such other spacing as will be found to be advantageous in particular installations.

The nozzles N are arranged and directed to the conduits 19 and 20 to provide a substantially continuous stream of air effective for the purpose mentioned above, and thus each nozzle N comprises a tubular body section 26 bent to provide substantially right-angularly related leg portions. The free end of one of such portions is associated with an opening 27 provided in the wall of the conduit 19, and preferably the tubular section 26 of each nozzle is then united to the manifold by welding, although resort could be had to any other suitable type of interconnection. One of the features of the present invention is an adjustment of the nozzles so that compressed air may be directed along selected paths in the space between the switch point and stock rail. Thus, the peripheral portion of each tubular body section 26 opposite that connected to the manifold is screw-threaded as indicated at 28, Figs. 8 and 9, to receive a hexagonal cap as 29. This cap has a screw-threaded opening 30 at one end thereof so that this cap may be threadedly fitted onto the screw threads 28 on the corresponding end of the nozzle as N. At the inner end of the screw threaded opening 30, a valve seat 31 is formed which has an opening as 32 extended therefrom and through the end of the cap 29 opposite the screw-threaded opening 30. 'Ille aforementioned adjustment of the nozzle in the present instance is afforded by an outlet member comprising a body 33 in the form of a ball which is provided with a boss 34. A port 35 is extended through the round body 33 and the boss 34 and terminates in a restricted discharge orifice 36.

The ball 33 is retained between the valve seat 31 and another valve seat 37 which is formed at the free end of the screw-threaded end portion 28 of the tubular body 26 inwardly thereof. In relating these parts, the spherical body 33 is passed through the opening 30 in the cap 29 to have the boss 34 projected beyond the outer end of the opening 32, and when the threaded opening 30 in the cap 29 is fitted onto the screw-threaded portion 28 of the nozzle, the outlet member 33 is clamped between the seats 31 and 37. When the cap 29 is loose on the ball 33, the latter may be set to any desired position in the seats 31 and 37 and this position then locked up by tightening the cap 29 in position.

As will be explained, air under pressure is supplied to each of the manifolds to be discharged through the 4, orifices 36 of the nozzles N associated therewith. A stream of air discharged from each nozzle as N is advantageously directed toward the upper surface of the adjacent portion of the base flange 38 associated with each rail, and preferably this stream of air impinges thereon approximately fifteen inches away from the orices as 36 in those instances where the nozzles N are spaced at fifteen inch intervals along the manifold. In order to insure that the stream of air will be so directed, it is advantageous to resort to a tool as 40, Fig. 10, which preferably is in the form of a rod of a longitudinal extent corresponding to the distance from the discharge orifice 36 to a point where the stream of air discharged from such a nozzle is to impinge on the base flange 38 of the rail. The tool 40 has an opening 41 formed therein of a size to receive the bosses 34 protruding from the nozzles. When a boss as 34 is then mounted in the opening 41' and the opposite end of the rod 40 engaged with the adjacent portion of the base ange 38 of a rail, the cap 29 may be tightened onto the tubular body 26 and thereupon the spherical outlet member 33 firmly secured in adjusted position. After this adjustment has been made, a stream of air subsequently discharged from the orifice 36 will impinge at the desired position. It may be found in actual practice that it will be advantageous to have a stream of air discharged from an orice as 36 impinge on the base ange associated with the rail at some position other than that which is described above, and this may -be expeditiously effected by loosening the cap as 29 once the corresponding boss 34 has been inserted in the opening 41 of the tool, and then the ball 33 can be rotated relative to the seats 31 and 37 to any desired position to cause the emitted stream to travel along the desired path.

If desired, an arrangement may be afforded whereby air under pressure may be continuously supplied to manifolds as 19 and 20, ybut in most instances this will not be necessary, and furthermore, it will be more economical to intermittently supply air to these manifolds at a definite rate and for a definite duration. Consequently, resort is desirably had to an arrangement including a control whereby air under pressure will be intermittently supplied to the manifolds to be intermittently discharged through orifices 36.

One arrangement to which resort may 'be advantageously had to intermittently supply air under pressure to the manifolds is shown in Fig. l wherein many of the parts shown are not drawn to scale. A pipe 41 leads from a suitable source of air under pressure, and this pipe is advantageously equipped with a shut-off valve 42 of conventional design so that air supplied to the blowing apparatus of the present invention may be shut off when and as desired. In some circumstances, it will be advantageous to control operations of the blowing apparatus from a very remote position such as a switch tower or the like, and in such circumstances, a solenoid operated valve may be employed in place of a hand-operated valve as 42 so that by controlling the operation of such a solenoid valve from such a remote point, control of the blowing apparatus may be effected from such point.

It is advantageous to filter air supplied to the blowing apparatus, for this insures against clogging of control valves and the like through which air is `to ilow, as will be explained, and to this end the supply pipe as 41 desirably leads first to an air filter 43 of conventional design embodying a filter 43S into which the stream of air flowing in the pipe 41 is deflected prior to passage thereof from. the filter to the blowing apparatus. lf desired, resort may be had to additional air filters, and it will be advantageous so to do in instances where there is a long extent of pipe through which the air must ow prior to passing through various means included in the apparatus.

Where the blowing apparatus is to be used to free a railway switch of snow, it will be operated in many circumstances at relatively low temperatures, and in order to insure that any moisture that might collect in the system will lnot freeze under such circumstances, and particularly to insure against freezing of moisture adjacent the discharge orifices 36 it is advantageous to introduce an anti-freeze solution in the system. To this end, resort may be had to devices which are conventionally employed to inject lubricants into air lines. In the present instance, such a device is indicated by 44 in Fig. 1, which includes a bottle-shaped reservoir forholding the anti-freeze solution F. A vertical siphon tube 44P in the reservoir opens at its upper end into a chamber 44C associated with a needle valve 44V and drip gland 44G that is adapted to be manually set for any desired rate of flow. An air tube 44T leads from the line 41 through a ball check valve and into the reservoir containing the anti-freeze F, and below the drip gland 44G the pipe 41 is restricted to afford a venturi effect for draining lubricant through the gland in-to the pipe 41 leading from the device 44. In this manner air passing from the air filter 43 flows through the injector 44 to have anti-freeze solution such as alcohol, diethylene glycol or the like introduced thereinto.

The pipe 41 leads to an air storage tank 45 and a manually operable adjusting valve 46 is provided in the pipe 41 to control ow of air to the tank 45, the adjustment of such valve being described hereinafter.

In order to insure against water collecting in the air supply line and tank 45, a water trap 47 is advantageously included in the supply line 41 desirably at the lowest point in the supply pipe, and in the present instance such a water trap is disposed between the adjusting Valve 46 and the tank 45. `,Any water standing in the trap 47 can be ejected under the pressure of the system through a stand-pipe 47P and a pet cock C of the usual kind. For static conditions, a drain plug 47D is aorded.

Air is discharged from the tank 45 through a pipe 48 which has a fitting 49 provided therein to which an air operated switch or pilot relay control valve 50 of a known type is connected. The switch 50, for instance, may be of the kind as described, for instance, in United States Patent No. 1,416,092. Thus, an air valve 51 is provided in the pipe 48 beyond the tting 49, and an air line or conduit 52 leads thereto from the air ,switch 50 to control the opening and closing of this valve 51, as will now be described. One form of the air switch 50 is illustrated in Fig. lA. Air from the fitting 49 passes through air lines 49a and 49h, in communication with the tank 45 through the pipe 48 and fitting 49, to a valve 50V that connects to the line 52. Air in' the line 49a impinges on a diaphragm (not shown) in the base of theyair switch 50 for controlling a spring biased lever 50L and a control plunger 50P for the valve 50V, the relation being such that clockwise and counter-clockwise movements vof the lever 50L about its pivot P effects opening and closing of the valve 50V, these movements of 'the lever SOL in turn being controlled by the diaphragm (not shown) and a spring 50S which tensions lever 50`L lat the top thereof. Thus, when a predetermined pressure is attained in the tank 45 and pipe 48 so as to be impressed on the diaphragm of the air vswitch 50, the valve 50V is operable to permit cornpressed air to ow as a control means through the conduit 52 to impinge on the air valve 51 to thereupon open the same, whereupon air under pressure may ow from the fitting 49 along pipe 48 and through the valve .51 tothe supply pipe 53.

The pipe 53 leads to a fitting 54 disposed outwardly of the stock rail 15, and conduit means 55, Fig. 2, lead from a fitting 54 to a nipple 56 that is passed through the ,web W. of the rail as 15 to be connected in the present instance to the manifold 19. A pipe 57 leads 'fromthe fitting 5410 a connector 58 formed from rubber"or""other `non-conductive material, the purpose of which will be explained presently. A pipe $9 leads from the coupling 58 to a fitting 60 and suitable conduit means as 61, Fig. 1, leads from this fitting to a nipple 62 passed through the web of a rail to be connected in the present instance to the manifold 20.

The conduit means as 55 includes a iiexible connection 63 and the conduit means 61 includes a flexible connection 64, Fig. 1. These flexible connections compensate for any movement that may be induced in the rails adjacent to which they are arranged such as may be attendant to the passage of railway equipment along such rails. Furthermore, the interposition of a coupling 58 of non-conductive material assures against an electrical connection being established between the rails 15 and 16 such as might interfere with the signal system customarily associated with the rails of railway equipment.

The pipes 53 and 59 are desirably disposed between adjacent ties as T, Fig. 1, supporting rails as 15 and 16, and again to insure against undesirable collectionv of moisture a water trap as 65,A Fig. 1, is provided at the lowest point iu the system of which such pipes are a part, as explained hereinabove.

The air operated switch as 50 isv part of a remote control for the valve 51 and is adapted to open to pass compressed air as means to control the opening and closing of the valve 51 when a predetermined pressure is attained in 'the tank 45, and is adapted to close to interrupt such a control when the pressure in the tank 45 drops to a predetermined amount as pointed out hereinabove. As` for example, the air switch may be, actuated when the pressure in the tank 45 and associated parts reaches pounds per square inch and may close when the pressure drops to 70 pounds per square inch. When the air switch 50 is operable through its 3-way valve 50V to supply a pulse of compressed air through the control line 52 to open the valve 51, air under pressure then ows from the tank 45 through the pipe 48 to the manifolds 19 and 20 to be discharged from the nozzles N thereof and this, of course, reduces the pressure in the tank 45 whereupon, as explained hereinabove, the switch or pilot valve 50 eventually will close, thereby shutting off the supply of air to the conduit 52. The control conduit 52 preferably has associated therewith an arrangement whereby air may bleed therefrom once the supply of air thereto hasl been shut oi by the switch 50 so that the air operated valve 51 will close very shortly after the supply of air to the conduit 52 is shut off, and this is afforded -by the valve 50V which when closed is adapted to bleed the conduit 52 to atmosphere.

'Ihe foregoing arrangement enables air under pressure to be intermittently supplied to manifolds as 19 and 20 and desirably the apparatus is so adjusted that' air `will flow to the manifolds to be discharged from the nozzles for a predetermined period of time and also so that air under pressure supplied to the manifolds and nozzles will be shut off for a predetermined period of time. In order that this may be effected, the valve 46 is adjusted to insure that air under pressure is supplied to the tank 45 at a rate less than that to lwhich air is discharged from the tank 45 through the pipe 48 and associated devices. Hence, the valve 46 serves in part as a timer for controlling the time period between successive pulses of compressed air through the valve 51. Moreover, an air switch as the switch 50 is equipped with an adjustable spring 50S 'for the lever 50L and nuts N for adjusting the valve 50V and the plunger 501, which enables the pressure differential to be varied, which is to say, the difference in value between the pressures whereat this switch opens and closes. By adjusting the switch 50 to increase such a differential, the time period during which air will be supplied to the manifolds and nozzles N may be increased, and conversely, this time may be reduced by reducing the pressure differential. Thus, to bring about a controlled intermittent supply of air to themanifolds as19 and 20 and thev nozzles as'N,'-t1'1' valve 46 and the switch 50 serving as a sensitive timer for the control on the valve 51 are each adjusted. For example, these parts may be adjusted so as to permit air to ow to the manifolds and the nozzles associated therewith for a period of four seconds, and the parts may be adjusted to shut o such a supply of air for a period of forty seconds, and it has been found that time periods of this nature are set in most instances to enable the blowing device to free the area between the stock rails and switch points of snow, sand, rocks, iron ore or other debris.

By resorting to an arrangement such as that shown in Fig. 1, the size of the tank may be kept at a minimum for furnishing a suicient volume of air for each blowing cycle which is obviously advantageous. For example, in an instance where manifolds as 19 and 2t) include up to thirty-eight discharge nozzles as N, the capacity of the tank as 45 may be sixty gallons.

While resort to a tank as 45 of comparatively restricted size is satisfactory in most instances, there are circumstances wherein it may be advantageous to resort to a tank of much less capacity. An arrangement enabling this to be accomplished, is shown in Fig. 3, and referring thereto an air supply line 41A is provided which desirably will be equipped with a shut-off valve as 42, an air filter as 43, and suitable means as 44 for introducing an anti-freeze solution to the air supply as explained in detail hereinabove. ln this instance, the pipe 41A leads to a fitting 66 from which a pipe 67 leads through a ow control valve 69 to a tank as 68 of materially restricted size, and in an arrangement such as that shown in Fig. 3, a tank having a capacity of two quarts may be utilized.

From the tank 68, a pipe 70 which is part of a bypass air line between the tank 68 and air-operated valve 75, leads to an air switch 71 which may operate like the air switch referred to in detail hereinabove. In turn, a pipe 72 leads from this switch to a fitting 73, and a pipe or conduit 74 leads from the fitting 73 to an air operated valve 75 which is also the nature of the valve 51 described hereinabove, thereby completing the by-pass air line between the tank 68 and the valve 75. A bleeder line 76 and outlet pipe 79 leads from the fitting 73 and has a valve 77 therein for a purpose to be pointed out below. The air operated valve 75 is included in a pipe 78 that leads from the iitting 66 referred to above, and a pipe 53A corresponding to the pipe 53, Fig. 1, leads from the air operated valve 75 to a manifold arrangement of the nature of that shown in Fig. 1.

The valve 75 includes the usual valve seat that is adapted to be opened and closed through the action of a plunger 75V. A diaphragm 75D is in position to be operated by air under pressure in the pipe 74 and is connected to the plunger 75V so as to drive the same. The diaphragm and its plunger are spring biased to normally hold the valve 75 closed.

The valve 69 can be adjusted like the valve 46 to regulate the ow of air to the tank 68, and this adjustment is such that air is supplied through the pipe 67 to the tank 68 at a rate slower than that at which air may flow through the bleeder Valve 77 to be discharged to atmosphere through the outlet 79. In accordance with this form of the invention, the valve 77 in the bleeder line `is adjusted to insure that when the air switch 71 is opened, compressed air as a control means as aforesaid may flow from the air switch through pipe 72, fitting 73 and conduit 74 to control the opening of valve 75 and to maintain this valve open for a desired period of time. In this regard, the air switch 71 opens when a predetermined pressure is attained in the tank 68 and closes when this pressure drops to a predetermined degree. For example, the switch 71 may be caused to open when the pressure in the tank 68 is approximately ninety pounds and may be arranged to close when the pressure in the tank 68 drops to approximately seventy pounds. When such a predetermined pressure is attained in the tank 68, the switch 71 opens, the control air is supplied to the valve 75 and thereupon air under pressure ows from the supply pipe 41A and through pipe 78 and 53A to the manifolds as 19 and 20 to which the pipe 53A leads. During the time that compressed air is ibeing so supplied to the air operated valve 75 to control the same, it is also being discharged through the outlet 79 in the bleeder line at a rate determined by the adjustment of the valve 77, and this results in further reducing the pressure in the tank 68 and associated parts to a predetermined degree Whereat the air switch 71 closes thereby shutting off the supply of control air in the pipe 72. Consequently, the control air under pressure in the pipe 74 and the valve 75 will then bleed out through the outlets 79 and the valve 75 Will close.

Here again, by adjusting the settings of the valves 69 and 77 and the switch 71 as sensitive timers for the control, air may be supplied to the pipe 53A and associated manifolds for a predetermined period and at a predetermined rate. Hence, air will be intermittently discharged from the nozzles of the manifolds as 19 and 20 to which the pipe 53A is connected, and a discharge of air from such nozzles will be maintained shut off for predetermined periods. If desired, this apparatus may be adjusted to afford a supply of air for a period of about four seconds and to maintain the supply of air shut off for a period of about forty seconds, but of course, resort may be had to any other time intervals as will be found to be advantageous or as the nature of the installation may require.

While resort may be had to pneumatically operated means, such as those described hereinabove to control the intervals between operation of discharging air from nozzles as N, there are circumstances where it may be advantageous to resort to electrically operated means for regulating such intervals. An arrangement suitable for this purpose is illustrated in Fig. 4 wherein a supply pipe 41B is provided which is similar to the pipe 41 and which may have a shut-off valve as 42, an air filter as 43 and also suitable means as 44 associated therewith for introducing an anti-freeze solution into the air supply. Where resort is had to an arrangement of the kind shown in Fig. 4, a valve, as 81, effective when open to permit a supply of air under pressure to pass to the manifolds as 19 and 20, may be located at a point remote from the source of air under pressure, and in such circumstances it may lbe advantageous to direct air flowing from a supply pipe as 41B through an air ilter as 80 located adjacent to this valve, air flowing from the air filter Sil through a relatively short pipe 82 to the valve 81 t0 be discharged therefrom through a pipe as 53B which may be directed to manifolds in the manner described hereinabove with reference to the pipe 53 and manifolds 19 and 20.

The valve 81 is of the solenoid operated type and includes a control mechanism 83 for the solenoid. In the form of the apparatus shown in Fig. 4, a bracket 84 is secured to the housing of the solenoid control to support an electrically operated timer 85 of a kind to be described in more detail below. For present purposes, the timer 85 is of a conventional design and includes means effective to hold closed an electric circuit for a predetermined time interval and alternatively maintain such circuit open for another predetermined time interval during a cycle of operation to respectively energize and de-energize the solenoid control for the valve 81. Desirably, the timer is so arranged that the duration of such intervals may be adjusted as desired.

Conductors as 86 lead from the timer 85 to the electromagnetic coil 83M included in the solenoid control 83, and during the time that the timer 85 is effective to close this circuit to energize the solenoid 83, the solenoid plunger or armature 83A is operated to withdraw the valve plunger 83V associated therewith from the valve seat 81S, whereupon air under pressure flows to and through the pipe 53B to the manifolds with which itis associated. When the timer 85 is effective to interrupt the circuit to the solenoid control 83, the Valve 81V closesfand remains closed for the period determined bythe adjustment of the timer 85. Thus, the arrangement shown in Fig. 4 may be utilized to bring about an intermittent discharge of air from nozzles as N for the purpose described hereinabove.

It will be understood that a timer as 85 need not be directly associated with the solenoid as 83, since the conductors as 86 may be made of any desired length. This'enables a timing device as 85 to be disposed in any remote location found to be advantageous.r Moreover, the timer as 85 may be of such nature as to control the operation of a plurality of circuits so that two or more solenoids as 83 for controlling operations of valves as 81 may :be controlled by a single timer 85 as will now be described.

- In Fig. 11 there is illustrated an arrangement wherein :resort may be had to a single timer to control the operation of a plurality of solenoid operated valves of the kind shown in Fig. 4. In this instance, a single timer 100 is used to control the cycling of compressed air to the manifolds as 19 and 20 of three different switches, switch No. 1, switch No. 2 and switch No. 3, each comprising a stock rail 15 and switch point 17. For switch No. 1, there is afforded a pipe 41E-1 leading from a source of compressed air, and there may be arranged in this pipe a shut-off valve 42-1, an air filter 43-1 and an injector 44-1 for anti-freeze solution, all as described above in connection with Fig. l. The pipe 41B-1 enters one side of a solenoid operated valve 81-1 which is identical to the solenoid Valve 81 illustrated in Fig. 4, and a pipe 53B-1 leads from the other side of the valve 81-1 to manifolds including nozzles as N associated with the rails 15 and 17 of switch No. 1. For controlling the opening and closing of the valve 81-1, a solenoid control 83-1 is associated therewith, and this is inserted electrically between the terminals of a pair of wires 91, which in turn are connected to a microswitc'h on the timer 100, as will be described in somewhat more detail below. At the low point in the pipe 53B-1 leading to the manifolds, there is provided a water-trap 65-1 also as described above.

, Each of the other two rail switches shown in Fig. l1 is preferably arranged inidentical fashion, and for this reason the description set forth above of the various devices associated with switch No. 1 need not be repeated in this regard.y It will' suice to point out here that solenoid v-alves for switch No. 2 and switch No. 3 are also controlled by microswitches on the timer 100, and thus there are separate pairs of conductor wires 92 and 93 leading from respective switches on the timer 100- to the solenoid controls 83-2 and 83-3, respectively. These switches on the timer 100 are Iin the form of normally closed microswitches that are cam controlled, and the operation of which can be adjusted for energizing the solenoid controls in any time relation. In the present instance, such is accomplished by means of a set of cam discs 101, 102 and 103 that a-re arranged at 120 intervals on the drive shaft S of a motor 106, and consequently the speed at which these cam discs rotate together can be regulated through the variable speed of the motor. Each of the cam discs includes a lobe of predetermined arc (about 115) and associated with each cam is a microswitch, SW-l, SW-2 and SW-S, adapted to bridge the terminal in each pair of wires 91, 92 and 93 for energizing the respective solenoid controls. Preferably, these switches are suspended from a bracket 106B attached as by a strap 106S to the motor 106. 'When the contact buttons of the switches as SW-l are on the lobes of the cams, the contacts are open, and thereby the valves as 81-1 remain closed. .As the motor 106 is effective to rotate the drive shaft 105 and the cams thereon, dwell portions of the cams are presented one by one to the switches, permitting closure and bridging of the corresponding contacts and in turn energizing the solenoids, effecting an opening of the Valves associated therewith to permit air under pressure to pass from the pipes as 41E-1 to the pipes SSB-1 and from there to the manifolds as 19 and 2.0 associated with the rail switch. Advantageously, adjustable cam pairs may be resorted to so that the length of dwell may be preselected to give the desired pulse. ferent time periods of operation may be selected for the solenoid valves, and the sequence of operation of the microswitches as SW-1 may be regulated. It will be apparent from the foregoing that by arranging the solenoid valves 131, 132 and 133 in parallel, a single microswitch and suitable cam control could be resorted to.

Where such a timer as is to be employed in connection with one valve only, a single cam disc will be utilized, and this is the case of the valve 81, the control 83 and the timer 85.

Where -such an arrangement as diagnammed in Fig. l1 is resorted to, a control panel at a remote control station is preferably utilized which includes a main on-otf switch 110 for the timer 100, this switch being inserted between the wires 112 leading from the source of supply of electric current for the timer and the controls associated therewith.

In order that the presence of pulses in the nozzles N in the manifolds 19 land 20 embodied in the three rail switches shown in Fig. l1 may be sensed and observed, a bank of indicator lamps 121, 122 and 123 is preferably arranged on the same control panel with the onoft switch 110, and these three indicator lamps are electrically connected by pairs of wires 121A, 122A and 123A respectively to return indicators or sensing elements 131, 132 and 133 respectively which can be in the form of switches which close accordingly asA the corresponding solenoid valves are opened, and remain closed so long as these valves remain open s/o that circuit to the indicator lamps 121, 122 and 123 is thereby closed and indicates both the duration and rate of the pulses of compressed air emitting from the manifolds associated with the rail switches.

Hence, while I have illustrated and described preferred embodiments of my invention it is to be understood that these are capable of variation and modification, and I therefore do notwish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as follow within the purview of the following claims.

I claim:

1. In a railroad switch installation which includes a stationary rail and a movable rail each having head portions engageable with one another in the course of operating the switch to a closed state and each having vertical web portions, an elongated tubular manifold for compressed air -secured to the vertical web portion of the stationary rail on the inside thereof and beneath the head of the stationary rail, said manifold extending parallel to and wholly confined beneath such head whereby the movable rail of the switch can close on the stationary rail without damage to or intenference by said manifold, a plurality of discharge nozzle means communicably connected to and depending from said manifold in longitudinal spaced relation along the length of said manifold for discharging compressed air obtained from the manifold into the space between said rails in the open state of the railroad switch to maintain such space free of debris such as accumulations of snow, sand and the like, a primary source of air under pressure to be supplied to said manifold, a storage tank adapted to receive air under pressure from said source and con- In this manner, difnected by pipe means to said primary source, pipe means connecting said tank to said manifold for supplying air under pressure from said tank to said manifold, adjustable valve means interposed in the pipe means between the tank and the primary source of air under pressure, a. normally closed air-operated valve in the pipe means between the tank and the manifold and normally eective to prevent air underpressure flowing from said tank to said manifold, an air line so connected as to be in communication at one end with said air-operated valve and at the other end with said tank to enable air in the tank to impinge on the air-operated valve to open the same and allow air under pressure to flow from the tank to said manifold, a normally closed pilot valve which opens and closes in response to air pressure differentials and which is interposed in said air line between said tank and said air-operated valve whereby when the pilot valve is opened air in said tank is enabled to flow through said pilot valve and said air line to impinge on said air-operated valve to open the same as aforesaid, and adjustable means Ifor regulating the air pressure differential at which said pilot v-alve opens and closes whereby the duration of time `during which the pilot valve remains open can be regulated independently to thereby regulate the period of time during which said air-operated valve remains open and hence the duration of the pulses of air under pressure emitted by said nozzle means, said adjustable valve which is located in the pipe means between said tank and said source enabling adjustments to be made in the rate at which air under pressure is supplied from said source to said tank whereby the time duration between successive openings of the pilot valve can be hastened or retarded independently to thereby set andk determine the time lapse between the pulses of air under pressure emitted by said nozzle means.

2. In a railroad switch installation which includes a stationary rail and a movable rail each having head portions engageable with one another in the course of operating the switch to a closed state and each having vertical web portions, an elongated tubular manifold for compressed air secured to the vertical web portion of the stationary rail on thc inside thereof and beneath the head of the stationary rail, said manifold extending parallel to and wholly confined beneath such head whereby the movable rail of the switch can close on the stationary rail without damage to or interference by said manifold, Va plurality of compressed air discharge nozzle means communicably connected to and depending from said manifold in longitudinal spaced relation along the length of said manifold and having openings therein for discharging pulses of compressed air obtained from the manifold into the space between said rails in the open state of the railroad switch to maintain `such space free of posed in the pipe means which connects the tank to `the primary source of air under pressure to enable the rate at which compressed air enters said tank from said source to be varied at will, a normally closed air-operated valvek in the pipe means connected to the manifold and normally effective to prevent air under pressure owing into said manifold, an air line so connectedas to be in communication at one end with said air-operated valve and at the other end with said tank to enable air in the tank to flow through said air line and impinge on the air-operated valve to open the same and allow air under pressure to flow to said manifold, a normally closed pilot valve which opens and closes in response to air pressure differentials and which is connected to said air line at an interposed point between the tank and the air-operated valve whereby when the pilot valve is opened air in said tank is enabled to flow through said air line to impinge on said air-operated Valve to open the air-operated valve as aforesaid, and adjustable means for regulating the air pressure diierential at which said pilot valve opens and closes whereby the duration of time during which the pilot valve remains open can be regulated independently to thereby regulate the period of time during which vsaid air-operated valve remains open and hence the duration of the pulses of air under pressure emitted by said nozzle means, said adjustable valve which is located in the pipe means connecting said tank and said source enabling adjustments to be made in the rate at which air under pressure is` supplied to said tank whereby the time duration between successive openings of the pilot valve can be hastened orretlardedindependently to thereby set and determine the time lapse between the pulses of air under pressure emitted by said nozzle means.

References Cited in the le of this patent UNITED STATES PATENTS 814,671 Burns Mar. 13, 1906 1,388,997 Greer Aug. 30, 1921 1,683,997 Strafus Sept. 1l, 1928 1,803,358 Schumann May 5, 1931 1,818,989 Griith Aug. 18, 1931 1,920,003 Chenault July 25, 1933 2,647,796 Ziherl Aug. 4, 1953 2,700,519 Gilmore et al Jan. 25, 1955 2,784,928 Logan Mar. 12, 195,7 

